次酉极因子的扰动界

矩阵扰动问题不仅对矩阵论,而且对控制论、力学、线性系统以及工程都有着重要的意义.主要利用矩阵特征值与奇异值的性质,对广义极分解中次酉极因子的扰动界进行研究,得到F范数下新的扰动界,并利用最新的换子不等式,对李仁仓的研究结论重新证明,该证明更加简短有趣.     

Z网络下新的推理算法在不确定决策中的应用

针对Z-number的模糊不确定性和概率不确定性推理,在Z网络模型的基础上对其推理算法上做出了一些改进.首先,在Z-number理论基础上对离散Z-number在if-then规则下进行最大熵方法处理的算法过程做出了一些改进,由于算法过程中优化模型获取的区间值概率随着给定数据的变化并不一定能满足最大熵方法中的约束条件,所以对这些区间值概率进行了优化.其次,基于Z网络的结构和概率推理过程,对利用Z网络获取区间值概率然后应用最大熵方法获得约束部分最可能的潜在概率分布过程作出了同样的改进.最后利用一个实例来说明改进后的方法的有效性和可行性.     

遗传中紧空间与散射分解

本文证明了可数仿紧(中紧、亚紧)空间有类似Junnila的刻画，遗传中紧空间不具有类似Junnila的刻画，并给出了每个散射分解有紧有限的开膨胀的充要条件．     

新型锚喷支护结构在萍乡矿区的应用

根据壳体结构的力学原理设计地下新型网壳喷层结构，大幅度提高喷层的抗弯能力，同时使喷层整体具有一定的可缩性，能承受强大变形地压及采动荷载，达到用较少材料又提高喷层支撑能力与让压的目标，较好解决了加强支撑、喷层合理配筋、简化施工作业、降低材料消耗等问题，在萍乡软岩巷道中进行了工业性试验。     

Michael-Addition Reaction of Malononitrile with a,β-Unsaturated Cycloketones Catalyzed by KF/Al_2O_3

The utility of fluoride salts as potential base in a va-riety of synthetic reactions has been recognized in re-cent years.1 However, low solubility of fluoride salts in ordinary solvents hampers their wide applications in organic synthesis. On the other hand, there has been increasing use of inorganic solid supports as catalysts for many years2 resulting in higher selectivity, milder reaction conditions and easier work-up. Especially po-tassium fluoride-coated alumina (KF-alumina) has been a …     

Broadband spectral shaping in a Ti:sapphire regenerative amplifier

A birefringent crystal quartz plate of known thickness has been used as a spectral filter for spectral shaping in a Ti:sapphire regenerative amplifier. The spectral profile of the amplified pulse ejected from the regenerative amplifier was observed while adjusting the birefringent crystal plate in the cavity. By altering the gain spectrum, the bandwidth of the regeneratively amplified pulse was increased from 18 to 35 nm by using a 0.34-mm thick birefringent plate. The output pulse spectrum from the regenerative amplifier neared the bandwidth of the seed pulse. As a comparison, we used a coated filter outside the regenerative amplifier cavity, and the bandwidth of the regeneratively amplified pulse was stretched to 28 nm. When the bandwidth was stretched to 35 nm, the pulse was compressed to 35 fs.     

浅谈高校院系门户系统及其应用

介绍了高校院系门户系统的概念,分析了院系门户系统的结构,探讨了院系门户系统的实现和意义。     

杨载诗歌浅论

杨载为元代中期著名诗人。与虞集、范[木亨]梓、揭傒斯并称为“元诗四大家”。本文仅对杨载诗歌思想内容及艺术成就作些浅略的分析。     

ICP－AES法测定富锗酵母中微量元素

本文采用美国ＬｅｅｍａｎＬａｂｓ公司中阶梯光栅光谱仪测定了人工培养的富锗酵母中高含量锗及镁、铜、锌、铁、钾、钠等微量元素，研究了富锗样品的前处理方法，样品加标回收率在９０％－１０３％之间，测量相对标准偏差：锗１０％，镁、铜、锌、铁、钾、钠等元素小于７％。     

两两序列比对的一种新方法

本文研究DNA的两两序列比时,提出了基于快速沃尔什变换的新方法。经过计算模拟分析可知,比对的时间复杂度和空间复杂度明显降低.